static-methods

Access to static properties via this.constructor in typescript

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but in typescript this.constructor.prop causes error “TS2339: Property ‘prop’ does not exist on type ‘Function’”. Typescript does not infer the type of constructor to be anything beyond Function (after all … the constructor might be a sub class). So use an assertion: class SomeClass { static prop = 123; method() { (this.constructor as typeof SomeClass).prop; … Read more

Difference between static function and singleton class in swift [closed]

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Sure this sounds confusing and can be debated. However, from the best practices i can put some suggestions. Singleton is usually used to create a resource intensive and one timer initialisation for instance: a database connector, login handler and such. Utility class are classes that only have static functions and variables. It should not deal … Read more

Why aren’t static methods considered good OO practice? [closed]

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Object-orientation is about three things: messaging, local retention and protection and hiding of state-process, and extreme late-binding of all things. Of those three, the most important one is messaging. Static methods violate at least messaging and late-binding. The idea of messaging means that in OO, computation is performed by networks of self-contained objects which send … Read more

How to verify static void method has been called with power mockito

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If you are mocking the behavior (with something like doNothing()) there should really be no need to call to verify*(). That said, here’s my stab at re-writing your test method: @PrepareForTest({InternalUtils.class}) @RunWith(PowerMockRunner.class) public class InternalServiceTest { //Note the renaming of the test class. public void testProcessOrder() { //Variables InternalService is = new InternalService(); Order order … Read more

c++ automatic factory registration of derived types

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I use a singleton with a member for registration, basically: template< typename KeyType, typename ProductCreatorType > class Factory { typedef boost::unordered_map< KeyType, ProductCreatorType > CreatorMap; … }; Using Loki I then have something along these lines: typedef Loki::SingletonHolder< Factory< StringHash, boost::function< boost::shared_ptr< SomeBase >( const SomeSource& ) > >, Loki::CreateStatic > SomeFactory; Registration is usually … Read more

Is there a way to force a C# class to implement certain static functions?

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No, there is no language support for this in C#. There are two workarounds that I can think of immediately: use reflection at runtime; crossed fingers and hope… use a singleton / default-instance / similar to implement an interface that declares the methods (update) Actually, as long as you have unit-testing, the first option isn’t … Read more

Python decorator as a staticmethod

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This is not how staticmethod is supposed to be used. staticmethod objects are descriptors that return the wrapped object, so they only work when accessed as classname.staticmethodname. Example class A(object): @staticmethod def f(): pass print A.f print A.__dict__[“f”] prints <function f at 0x8af45dc> <staticmethod object at 0x8aa6a94> Inside the scope of A, you would always … Read more

How can I dynamically create class methods for a class in python [duplicate]

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You can dynamically add a classmethod to a class by simple assignment to the class object or by setattr on the class object. Here I’m using the python convention that classes start with capital letters to reduce confusion: # define a class object (your class may be more complicated than this…) class A(object): pass # … Read more